In the original game there was the possibility to insert CD2 directly, so that you skipped the intro video and got your savegames displayed directly. In addition, all options were loaded directly.

I do not mind to see Hobbes constantly at the beginning :), but is that also possible in the GOG version (possibly using a command string)?

I think this is the information you're looking for.

https://www.dosbox.com/wiki/MOUNT#Mounting_multiple_images_.28ISO_or_CUE.2FBIN.29

Thanks, but unfortunately that doesn't work because the DATA file from the original CDs must have been combined from GOG into one file that is mounted.