Crash with Upgrade

[fbfree]

Simutrans v. 110.6 Experimental 9.12 on linux x386 with pak-brit-experimental 0.8 crashes reproducibly when selecting a vehicle in a depot, then selecting 'Upgrade'.  If there is an upgrade available, the screen refreshes to show the upgraded vehicle prior to crashing.

[jamespetts]

Thank you for the report - I have now found this problem, which will be fixed with the next release.