The Compaq Portable II is a really weird computer. I've found a few blog entries and videos that are supposed to explain how this is supposed to work but none seem that helpful. So I decided it'd be nice to make a complete how-to for people that can't figure out how to get their Compaqs working(like me a week ago). All disk images required can be found at the bottom.
Before I begin, a huge thanks to @wierd_w for helping me get the Compaq working and sending me the diskettes nd various images i needed to get the machine booted.
You will need: A perfectly functioning Compaq Portable II(obviously), any cf2ide adapter, some kind of cf card(i used a 512mb one), the Compaq diagnostic disks on a real floppy disk, and the Compaq Fastart disk on a real floppy disk, a Disk Manager 5.22 disk image(a physical copy works too).
Before you start messing with the floppies and cf card themselves, you'll have to set up the cf2ide adapter and pull out the original hard drive(if it came with it) because the thing is HEAVY! If you need help doing that, just go ahead and sell your Compaq. After everything is set up properly, format your cf card on your modern computer, then stick it in the cf2ide.
Now the upcoming step is just luck. If it doesn't work on your Compaq, then, well, sucks to be you. Anyways, run the setup program on the diagnostics disk, and hopefully it'll detect some kind of fixed disk type. Mine detected a 34.1mb fixed disk drive(type 14 iirc), which is good for now. Save and exit, then use your fastart disk to partition your card. It shouldn't be too complicated. Don't install anything just yet because it's about to get deleted on the next step.
Once the card is partitioned, shove it into your modern pc, then copy the Disk Manager program onto the card. The download link gives you a disk image so you'll have to extract it with winimage first. Insert the card back into your Compaq and run DM.exe. Once you've initialized your disk in DM, your cf card should have all of its capacity available for use(that is, if it's under 512mb I think. The Compaq can't detect anything bigger than that, but I might be wrong because I haven't tried.) Regardless, it's plenty.
Once the disk is ready copy the Compaq DOS 3.31 files onto the card. Use diskinit to install MSDOS onto your card. This should cut your card's size to 314mb, but the pros outweigh the cons. 314mb is plenty anyways.
Well, that's it! Now you can install whatever stuff you want to onto that card and the Compaq will run it:) I'd recommend you install whatever version of Windows. If you have a 640k system(like me) Windows 3.0 should run fine but if you have extended memory you're welcome to go ahead and install a better version of Windows.
By the way, I may have forgotten something somewhere in the middle, so if you have any questions, concerns, or error reports feel free to dm me:)
Compaq DOS Disks
Compaq Fastart Disk
Disk Manager 5.22
Rawrite; a disk imager for DOS systems(so you can run it on your Compaq and create your own physical floppies from disk images)