Unable to Migrate files and apps (from Time Machine) post Sequioa install (MBP late 2013, via OCLP 2.0.2) - stuck in boot loop with nothing migrated.

I have tried the following:

1. Install Sequioa via OCLP, write bootloader to internal disk, run patches, attempt to migrate Files and Apps from Time Machine
2. Install Sequioa via OCLP, write bootloader to internal disk, revert patches (to ensure none are installed), attempt to migrate Files and Apps from Time Machine
3. Install Sequioa via OCLP, in the Set Up assistant (i.e. before desktop is set up and before it even loads), attempt to migrate Files and Apps from Time Machine

In all three cases, I get a message akin to 'Migration successful, now restarting' - after which the macbook gets stuck in a boot loop. If I hold down Shift, I am able to enter safe mode, go through set up and reach the desktop, though none of my 100gb worth of migrated files are seemingly there (neither are any of the apps). At this stage, even if I write the bootloader to internal disk, and after, run patches - the laptop will still revert to that same boot loop.

Any thoughts or suggestions?

Furthermore, when I did the backup, I foolishly thought if all failed, I could reinstall Big Sur and all of my files using the Time Machine backup I created pre-OCLP, though when I try to do it, it says I need to install an OS first which is annoying.

I would be happy to copy over the files I want to keep from Big Sur to a HDD, and then manually copy them over to Sequioa (OCLP) - though it seems I now can't even do this!