Bugs causing crashes are simply unacceptable. So the OS file selectors are a no-no for me. Period.
Yes, how shocking, it's just a plain file selector... Sue me ! Or get to the work and add those features to it yourself (nothing prevents anyone from doing it: the sources are GPL and well documented, and also, unlike LL's implementation, very lean and clean).
The only option for me was to get fully rid of the OS-specific dependencies (GTK for Linux, Carbon/Cocoa for Macs, infections/DLL-injections-sensitive Windows file selector). So, no, it's not possible to make it optional.
Yes.