Still can not get to crash - tested older Ubuntu 64 bit and newer Debian 32-bit.

So I will give up for now and maybe later an inspiration for a different solution will come up.

I tested ot like this.

load some jpg image, it will expand itself as default 3 sec long timeline.

"Save as" with xml extension.

Load this xml as nested.

hit 'undo' right away.

for me cingg crashes :(