General

BIOS/XBIOS
- implement missing XBIOS calls (e.g. Falcon DSP functions)
- reduce the number of 'extern' in .c files
- check that RAM disks work
- misc. TODOs in floppy.c
- implement full XHDI 1.30

BDOS (GEMDOS)
- move mem-only routines out of proc.c into umem.c or iumem.c

VDI
- The linemask for dashed lines is not calculated correct, depending on
  the internal calculations of increase in x direction, like in original TOS.

AES
- Implement AES v3.x functions (TOS v3 menu functions and v4 3D look)

DESK
- Add a dialog for configuring the NVRAM (keyboard, languages, ...)
- Support for loading DESKTOP.INF (needs remapping of the icon indexes)

CLI
