I had to go into the motherboard 'bios' and switch the motherboard to 'Legacy Mode' to install eCS 2.2b2 on my ASRock 970 Extreme3 R2.0. No surprise there I expect.
I believe that is a listed requirement. Yes, you do need to use "Legacy Mode". This is an old OS after all.
1) Loading of the virtual floppies into RAM would stall around 2/3rd the time on varying installation disks (1st, 2nd or 3rd),
I haven't seen any problems with that, so far. Of course, I never saw a problem with that before either.
2) There was a problem with selection of system drivers (I forget the details)
Since it is a new installer, it will need extensive testing.
3) Either the onboard laptop keyboard or the laptop touchpad would not work, sometimes both, sometimes the problem would switch from one device to the other.
I haven't tried on a laptop, yet. I will keep this in mind. If I get my way, the touchpad will be turned off, but that is irrelevant for testing. My Lenovo ThinkPad T510 has a switch in BIOS to do that. My Lenovo ThinkPad L530 has no such thing. In windows, I can turn it off. In eCS, I cannot do that, and it is a PITA. I may put in a feature request.
I ended up disabling the two USB3 ports and reverted to USB2 in 'bios', attached USB keyboard and USB mouse but was unable to access a USB floppy drive to load in the eCS key. Only two USB devices worked at a time.
USB has not changed, yet (don't know if it will, or not - probably not). USB 3.0 support is definitely unlikely (AFAIK, the project has started, but no progress, yet).
Sounds like you need a USB hub, to allow more things to plug in, but that is really not something that any installer can address.
I will note, that it is possible to add stuff (like keys) to the DVD, when you burn it, if you do it carefully.