My first computer was also an IBM "Thinkpad". Similar probs there.
Slowly running websites, slow Google earth/maps picture buildup and zoom.
Movie maker didnīt work when inserting effects or transitions ....etc
Thatīs the reason ( and a damaged screen) why Iīve  purchased a PC.
Seems it has to do with MY adjustments.

great music on this one !
Sounding very organic to me

vids is a nice job too, but I do think u used too many effects.., not strange your pc doesnt handle this maybe?
Its not too bad to watch a good pic a few seconds without it moving all the time..
And then the timed effects come out stronger..
Liked that iron guitar man during the git solo much

Tnx, M(arino). & M(ax). (eminem??) for your listen and comments.     Always appreciated.

Yeah, I was also fascinated of the "iron man". The right sculpture for the git solo.

About PC: Iīm not sure if the amount of effects is responsible for stuttering pics (not basically), cos the preview on the timeline was also stuttering without any effects. And the insynchronity of audio and video under increasing duration appeared already when I worked with WWLM.
I guess thereīs a deeper, fundamental issue somewhere in my PC . Either a software prob (virus, malware) or itīs a hardware prob. Thatīs my assumption.
Weīll see. ...........................

Brought my PC to the store for reparing.. It took almost 3 weeks  until I got it back yesterday.
They changed the mainboard.
Hope it will work better now.