Alright, I've looked into all of your remarks and found out the following:
1) There were a few bugs when checking for dialogue triggers. Dialogues should be played correctly now. If the problem persists, I will need more information on how to reproduce this bug.
2) Both shops have been revamped now. They should open the last tab that you were on (only during runtime, the tab won't be saved after you close the game) and I've made other changes to optimize the script.
3) This feature isn't 100% reliable. I haven't found a way to make sure it works everytime, but it does work sometimes. I've made sure you can click and hold all "buy all" buttons of which there are a total of four and for every upgrade you can buy, meaning you don't need to click multiple times, when you can afford multiple levels of an upgrade, just click and hold.
4) I can't reproduce this bug, it seems to be working fine for me. Not sure what I did wrong.
All of these changes will come with the next major update, I'm already preparing and testing everything, it shouldn't take more than a few days.