Thanks for the replies everyone!
Finally had some more time to fumble around with it today. Well at least a few minutes.
The machine is a real oddball if you compare it to other DOS based palmtops like "Poqet PC", "HP 200LX", "Sharp PC-3000", etc. At first it was extremely late as it came out in 1994. So you would expect DOS 5 or 6, but not MS-DOS 3.10. I guess the Japanese DOS 3.10 was kinda special since it displays all messages in "proper" Japanese, meaning it uses the complicated Kanji characters, not just Katakana and Hiragana (these are a bit easier to read for me, my Japanese is not that great).
And also it has a quite custom Japanese keyboard, so no real alt, ctrl and other keys, which makes it a bit hard.
I managed to get 3 appz from that ftp running, so I know it has an 80286 processor which was a surprise since other plamtops rather have a 8086 clone CPU. Also it accepts a 4MB SRAM card which some other palmtops with later DOS versions rejected. I also tried Flash cards, but no luck. But i believe with the appropriate driver it might be possible.
I think the reason that most appz crash is the weird Japanese GUI that starts up first, so DOS is only used as a "shell". But since i can edit the autoexec.bat and config.sys I think i can get rid of that. Also i can install a driver for Flash cards that way.
I believe it has at least 1MB RAM since i have like 500KB free memory and some drives mapped which seem to be kinda RAM disk. So maybe possible to use some EMS as well. I don't expect wonders, but i enjoy understanding and getting most out of such neat old machines.
