My reply is likely.. really long... bear with me.
The game now asks your Save-file where crystals and horse are saved - because they were never, ever written to the save file, and always spawned by the game/engine - they have no location saved, they don't even exist according to your save file... so. the game "loses them"
The game /does/ spawn one on a fresh save, so that your save file knows they exist and will track their location.
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Lamp on Cart is for seeing from the cart and nothing else really, which isn't recommended, as the horse is still extremely buggy - recommend only using the horse as you did in 0.81 - riding it has its own issues.
Riding it can, especially if it freaks out, result in character model desync
Character model desync results in character sheet desync. Which /can/ be permanently written to save http://mlbs.slipcor.net/ has a Player Model fixer, which should fix sheet desync as well
Horse desync can (maybe) be fixed from the fixer underneath the Player model one, in case the horse/cart are currently jumping over the moon.
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Mining - A) darkness intensity is controlled in part by graphics, and can be lessened with lower graphics. Keep this in mind
B) Lantern ontop of workbench wall-shelf - Instead of carrying it, Shove it into the box you plan on mining with
This reduces the overall light, but you get a Mining crate, which provides light, anywhere you stick the crate near.
C) Alternatively - Use the Light Crystal, saves crate room for more ore, and lights /almost/ as much (not as far a light range, not quite as bright)
D) Alternatively, you can /actively trigger/ that "item stuck" you're talking about (hold item, hit esc, release item, return to game, hold item again - item is now adhered to location you grabbed second at) (If you skip hold again, you can "toggle" holding it, so you don't have to keep the mouse button pressed - any other button than grab, releases it.
You could use this to set up crystals and the lantern in a way that act as a guiding path of light in the cave, Above you, so its both out of the way, and higher better lighting. - I of course, don't recommend this, I use the Light crystal in my crate.
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Items stuck by aforementioning bug/glitch - can be destuck by using a crate's lid, Enclose item with crate, lid, unlid - item is free. - Harder to do if you can't get a crate around it.
However. On reload, most items "grabbed" by you, either once, twice, or etc - will be "ungrabbed" because /you/ left the equation, and /you/ are required for "grab" - they become normal/unlocked after that.
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Geofreys
... Just.. Don't use his shop, he's a swindler.
A) The Shopping basket, The Basket is its own item, and the crate you get outside, is a different item - When you lid it inside, you're lidding the basket, something you can never unlid when you get outside... because it swaps itself with a regular crate. - This is why if you take the crate back inside, it will never show a new pricing on the side - its /not/ a shopping basket, anymore. - If you don't lid the basket, you won't glue the items inside when you get home.
B) Lidding has its own issues as well - as the game sees lidded items as a separate set of items - So even when you reload and free the items from Geofrey's crate basket (basket crates despawn on reload, and because the basket no longer existed anyway, the item stop being physics disabled by it) - You're charged a second time (or at least, I felt like I was when I did this.) - this is because you never bought the unlidded set
The same applies for your own crate, or using the basket crate later. - If you leave with lidded items, those are the items you bought, unlidding it and using the items later, results in "Stolen" labels - which, seem to currently not be fully implemented- there's reports of people still managing to sell them to npcs. - but the game still sees it as "you bought the lidded set, how did you get that unlidded set outside of the shop without paying?? Stolen. Stop right there, criminal scum!
if your shop basket pricing gets "off" that too can result in "stolen" and the pricing is easy to be "off" and we likely never noticed it before because there was no "stolen" or other reasons we would notice it - But items leaving the basket results in infinite game breaking - as they don't calculate correctly.
- Its easiest to forego using Geofrey and just order handles.. but alternatively
- Go into Geofrey's shop
- Take a single item, place it in his basket (this will allow the basket to actually be liddable, it can't be lidded at all if you just carry it out, empty)
- Carry it out, unlidded (you can test lidding inside just in case you don't feel confident it will be liddable outside, just make sure the lid is off when you leave.
- Go back in, take items to doorway and push them out of shop - one.. by one....
- This will (hopefully) prevent stolen, and ensure you pay each items "correct price" - and prevent glue/temptation to lid basket. (which is now already a crate)
- Put now purchased items into now crate...crate - Keep in mind, if you lid this crate, it doesn't properly "disable physics" on the items inside, - be /gentle/ with it, as you could cause physics richochet on the inside which can keep the crate "unstable" when you set it down, or worse, they could explode out of the crate (harder to do, but possible if you rile up the engine enough)
tl;dr
Don't ride cart - buggy, use horse at discretion - still buggy
Don't use Geofrey unless you're uber delicate and careful.
Don't use lid inside of Geofrey's shop and then leave.
Don't hold an item - then hit esc - then try and hold the item again when you return - applies for any item, anywhere, anytime.
Additionally. Try and make sure you sleep between 9-11pm in game, before quitting.
The game forgets exhaustion/sleep schedule when you quit
If you say, quit at 9pm, instead of sleeping.
You will stay "untired" for the next 16hrs (After 1pm - you can go to sleep, and by 9pm again, you'll reach critical fatigue/level 2)
Quitting however, doesn't reset "ailments" - If you were fatigued, and couldn't run before quitting, you will be unable to run after reloading, even though you're now "no longer tired."
Prevent this by sleeping, before quitting, or at least only quitting at 5-7AM
For everything else you have or haven't encountered yet, I suggest checking K's Bug list - the 2nd post has the Bug List (mostly) as seen on Trello, but with the additional information known about cause/fix/workaround.