Hello!! I'm so sorry to hear that you've been having problems! Are you playing on windows or mac?
Also you can pick it up whenever you like even after multiple restarts, you don't have to go to floor 6 straight away!
Alright! In order for your game to run as it should it needs to be able to autosave itself but for the mac version if you download it the wrong way the saving function doesn't work at all, ultimately fully resetting every time you die without remembering what you did past run!
I wrote it in the download instructions that when you download the zip file, you need to extract the zip file into a folder- and when you open the folder, drag the "game" file (only the game file not the entire folder) out from that folder and into your applications folder. Once you get the game file in the applications folder, try to open the game file there- if it doesn't open continue clicking until it does and it'll eventually let it run. If you did this the right way then your game'll be able to save and let the game run/progress normally! Try redownloading and follow those steps again? Hope this was helpful!!