Ok here's my hacked solution...
I've concatenated the combobox references with carriage returns, and set the text box property 'Can Grow' to true. Now if more than one box is checked, the cooperatives are listed vertically (not ideal, but close enough).
Code:
=[Forms]![FormName]![cbo] & Chr(13) & Chr(10) & [Forms]![FormName]![cbo2] & Chr(13) & Chr(10) & [Forms]![FormName]![cbo3]
The problem I had here was that the Page Header wouldn't grow with the growing textbox. For reasons I may never understand, the Page Header has no Property "Can Grow." The solution is to create a new arbitrary Group Header, which does support the Can Grow Property.
New problem! If a user checks queries based on 2 or more cooperatives, then reverts back to one -- the names of the 2nd or 3rd cooperatives are still shown in the report. I need to to do a conditional on the checkboxes. I keep getting back an error that I have the wrong number of arguments.
Code:
=[Forms]![SpeciesByLCC]![cboLCC] & IIf([Forms]![SpeciesByLCC]![check1]) Then Chr(13) + Chr(10) & [Forms]![SpeciesByLCC]![cboLCC2]
Thanks!
Roy