Hi Sigurd. Interesting project...
1. It would be interesting to see if GENMAC 2.1 (from the eCS 2.1 install CD) would do it right (probably not, since it seems to be a config.sys sort problem). It would also be interesting to know what happens if you use my Logical ConfigSys Sort program (LCSS) on those machines. It is at HOBBES:
http://hobbes.nmsu.edu/download/pub/os2/util/config/LCSS-0-4-4.wpi You may need an updated DAT file from:
http://www3.telus.net/public/bissett1/LCSS.dat.
2. I have decided that the Sunny Icons feature causes too many problems, so I simply don't install it (I will try again, with the GA version). There is a selection in the desktop properties to turn that off (Display-> turn off Default, and select Normal). It doesn't seem to prevent other annoyances that I have seen with that feature.
3. I have quit installing DOS and WinOS2 support. It seems to be pretty useless these days. I agree that DOSBOX does a reasonable job, for the few times that I find a need.
4. I have same problem on my T510, and my L530, and I do miss it, on the few occasions when I would like to use it.
5. Sound works well, on my T510 (if you don't count the terrible speakers), using UNIAUD from UniaudUpdate1.09.06-2.02.01.zip. I get sound from the L530, using the same driver, but it is not right. Earlier versions of UNIAUD won't even load. So far, I haven't bothered trying to get it fixed, since there are other problems on that machine.
6. USB works well on the T510, using Lars' versions. The T510 has two EHCI adapters, and no others. USB also works well, on the L530. The L530 has a USB 3.0 adapter (which doesn't work, of course - even in windows, until you turn it on), as well as two EHCI adapters. Lars' driver works, and I can use all of the USB ports, including the USB 3.0 port, with USB 1.0, 1.1, and 2.0, devices.
7. That may have something to do with sound support (just a guess).
8. I haven't seen that feature...
I will add an observation, and question:
9. My L530 has a UEFI BIOS, set to "legacy" mode. It runs eCS 2.x okay, but there is a 4K memory hole at the 512 meg mark (cause unknown). That prevents eCS from "seeing" more than 512 meg of memory. From what I have been able to determine, some devices also cause memory holes, but the rest of them are above the 3 GB mark, so they wouldn't cause a real problem. Does your X230T have the same thing? FWIW, the L530 does run well, with only 512 Meg of memory.