This will be one of the main things I use an Octatrack for so does anyone else use it for this? Recording synths directly, what are the technical steps?
And is it even possible to record them if you’ve sequenced and P-locked them?
Does everything record straight to the CF card?
You should read the manual on how to record into the OT, or do a Youtube search for a tutorial for basic recording into the OT.
I’m not sure what you mean here. That said, if the synths have been sequenced with MIDI tracks in the OT, their audio outputs can be connected to the OT’s input, and recorded.
The OT records to memory. A user then has to save the recording to the CF card manually.
Sorry, but again, I think you may need to invest some time into reading the manual.
I thought there was hardly any memory? 84mbs.
Does that mean recording is limited?
Looks like you already got the answer:
Each project can record up to 85.5mb, as stated by @malus_mons. That is still a good amount of RAM. If you keep in mind that 1mb of RAM is roughly 1 minute of mono audio at 16-bit 44.1kHz, you can have a better idea of how much you can record fr a given project.
Yes. It’s about 8mins worth.
I’d say the core sampling feature set is tailored towords live manipulation of live samples… like a looper pedal with 8 simulatanious channels and crazy, performable, FX. It’s much less like a “build kits of samples” type sampler (although you can also do this). Despite the feature list, it’s not really like a DAW at all.
You can sample a MIDI sequenced synth, yes. You could even “transition trick” it… sequence a pattern, live sample it, swap from the incoming “live” sound to the sample, perform manipulations on the sample, then flip back to the incoming sound.
OT records in stereo only.
Yes. But you can also record your mix internally, if you use short samples in RAM.
I record in mono often by choosing a mono input…
OT still makes a stereo file from this.
True, and very useful. It’s more like a DAW than I made out 
(I was trying to emphasise that although the OT does a lot of things you can do in a DAW, and in other samplers, Elektron’s decision to make a “live performance sampler” kinda dictates the quirkiness and limits/workflows when you want to do other things with it. )
Damn, you’re right. My bad
The UI hides this from you: the AED shows a single channel even when you load a stereo sample (maybe you can set it to show two channels with an option - I’ve left my OT in its box all year so I’ve forgotten some details).
Well, I just kind of power through without thinking about mono, stereo, and the RAM space they use, so I’d forgotten what the manual said. Plus I’m also thrifty with the OT by nature so limitations hardly ever impact me, haha. Oh well, that’s fault.
This is the way.
Probably a good time to mention to @Acidizer that although you can’t record direct to the CF card, you can play back from it it. You can play back gigabytes worth of audio from a single file, if you want.
Tracks have independent Recorders and Machines. The Recorders record to memory. The Machines play back recordings, or process audio live from the inputs (or from other tracks). The Flex (and Pickup?) Machines play back audio from RAM, the Static Machines play back from CF Card. Because Recorders and Flex Machines both use RAM, they have to share it. There’s settings to allow you to control the sharing - by reserving bits of memory for specific roles, or turning off the reserve.
OT was directly inspired by MD UW’s RAM machines (1 for recording, 1 for playback), definitely live oriented, with its 2.2MB RAM !
I usually set them to NONE, as it reduce available RAM for recording and FLEX slots.
Some people use it to record a defined length.
Limited to 508s (16 bit), which corresponds to 8m28s, 254 bars at 120 bpm.
Enough to record a few loops imho.
Yes. I do. And many more people.
This is repeated ad infinitum all over the internet, and it also appears in the manual.
Yes.
No. Samples are recorded to RAM. And can then be shifted to CF card. RAM is cleared everytime you power off the machine.
CF card contents are yours to keep and back up as many times as you like for as long as you like.
No doubt 
that’s good enough for me 