Simply by reading the log it states, that maps are missing, not that additional malformed maps exist. So, I'm uncertain where your assumptions come from.
Furthermore, I have been experiencing the same issue, after updating an old install as well as a fresh install of SR.
When tabbing out, the client will not close immediately as it will freeze and stuck before reaching any of the ERROR log messages.
Also by going through a Process Monitor log, there are a lot of File queries resulting in "Path not found", which may or may not be related.
The exact exit status code: -1073741819
Furthermore, a specific path and file related to the game which aren't found: "[RootDirectory]\Skylords Reborn\bf1\map\UG\"
"[RootDirectory]\Skylords Reborn\bf1\map\PVP\12601_PvP_02p_Skjal2.map"
If you require the Process Monitor log, please contact me separately as it's significantly larger than the allowed upload size. (ca. 40mb)
Going through my own memdump, I can see that a memory corruption occured.