TL;DR: (If old ver. TF2 Lawena user) Turn on offline mode in steam before launching old ver. of TF2 with Lawena. When done, go back to online mode to play current ver. TF2.
Use "tf_viewmodels_offset_override 10 0 -10" in "Advanced" > "Custom Settings..." to compensate for "tf_use_min_viemodels 1" not working.
Another step
been working on the HUD and video, suddenly new tf2 update comes out 2023-10-09. unlucky it's another update that affects my demo recording. not the game files this time but something to do with server stuff and versions.
i can't confirm 100% this is the case but seems this way: if internet connection on, steam client open (not offline mode) and if running old version of tf2 (specifically via Lawena launch), game will crash. even if you start game in steam's offline mode then leave offline mode while game still running, a second or two after the game coordinator connects, the game crashes. just in case, will make post on youtube to see if anyone else has this problem - is more inconvenience than stopper.
this time not as bad, can still record demos fine like before but have to either go offline mode every time i want to record demos on my older installation of TF2. use steam chat on browser if more convenient or if using old version of steam client where chat doesn't work anymore.
Theories
this issue seems it could be an incidental oversight of something to do with TF2 game coordinator being updated drastically enough that the old version doesn't know what to do when it's connected to, so it crashes. considering how many years you could potentially run old tf2 to play your demos, it seems more likely an unintended thing rather than some sort of anti-cheat thing. i use a tool, technically a "cheat" (+ Lawena) to get the camera angles you see in the videos but nowhere like cheating in-game with the automated sniper aimbots that ruin live games. servers already reject you if your TF2 version isn't the same as that server. regardless, it's another (albeit annoying) step to the process.
valve and tf team keeping me on my toes.
Viewmodel offset fix (Lawena) + other things
Demo playback without internet connection makes "tf_use_minviemodels 1" useless for non-stock weapons.
Use "tf_viewmodels_offset_override 10 0 -10" in Lawena > Advanced > Custom Settings... to have that command automatically apply everytime you run a demo.
This seems to also fix picked up weapons from other players too (as it should). However, decals won't appear for old demos should the game coordinator remain incompatible. Hats and weapon skins/paints still work.
compatibility.
Some screenshots of video wip
cam shot to show more to viewer, not normally visible in firstperson but sometimes won't if unnecessary or want to mirror my surprise
Centered HUD customization for split screen
Centered HUD customization in action, cropped for the effect