Hi Udo,
> I don't know if the subset, implemented in the FS2,
> is sufficient to allow for this desired sort of guiding.
The subset of LX200 commands in the FS2 should be sufficient for all
autoguiding programs. The Pulse-Guide command is not yet implemented in
the FS2, if you need it then you can use the relay box.
About the GuideDog software, Hansjörg Wälchli has written a small
article about it:
http://www.astro-electronic.de/software.htm
I have tested AstroSnap with good results.
Michael