I keep all my files in SD card/DOS, the original Constructor files are in “SD Card/DOS/Construc” however the “SD Card” part is an 8 digit ID like 8AHF-946T.
I haven’t changed anything with the file system on either my phone or tablet, everything is default. I did check the read/write status of the settings files with Total Commander and they’re all good.
I keep everything I boot in DosBox inside that DOS folder and everything else I have launches and loads/saves without issue. I’ve got multiple Win95 images, then a bunch of DOS games including stuff like Sim City, Master of Orion 2, Transport Tycoon etc.
I couldn’t get the other couple of free DOS apps to work Alex, couldn’t find the correct directory to type to mount the game files (the user interfaces were extremely basic).