I don't know if I'm allowed to post here, but I guess if you reading this, then the answer is yes!
One clarification to Warren's post above. You can use Invoice History and Adagio Order Entry together without any problem, as long as you set the number of days to keep orders alive in OE sufficiently high (I like 30 days).
Invoice History doesn't require any special files or procedures to integrate, it simply reads the OE Header and Line files, and synchs itself. So it doesn't care whether it is looking at a Plus or an Adagio OE database - they are identical for it's purposes.
Steve Schwartz