Not sure if this is a bug (broken) or an RFE
I run mrxvt with one of two different configuration
files, which results in my terminal command being
'mrxvt -cf /path/to/myconfig'. With no, single, or
double quotes, this fails when setting it in
Edit>Preferences>Terminal:. I stuck the command line in
a wrapper script so I could invoke 'wrapperscript' and
that works, but it's kind of a waste of an inode.
Looks very promising in general, though.