Check the Select statement in your Connector module. There is something weird about how it's selecting dates and for what it's worth, I do suspect that it's something bizarre about the underlying data structure in Sage.
For example, in mine, I have a Container called GL Transactions 1-0. I get a error message, however, if I go to the Source Container (Join) field, and delete references to the date, the report in RM will run, at least.
For example, I change this:
GL_DetailPosting,GL_Account
WHERE
GL_DetailPosting.PostingDate >='@StartDate@' AND GL_DetailPosting.PostingDate <='@EndDate@'
AND
GL_DetailPosting.AccountKey = GL_Account.AccountKey
to this:
GL_DetailPosting,GL_Account
WHERE
GL_DetailPosting.AccountKey = GL_Account.AccountKey
And the report runs without trouble.
Yours may be different, of course, but you get the idea, at least.
Usual cautions apply, ergo, copy the original statement to Notepad and save it before editing it so you can go back if it's merited somehow.
Lou