This is an old post that no-one had answered, but I was having a similar issue and so thought I'd post my solution in case anyone else comes across this.
It seems that Case function can't handle inequalities, seems to only do a simple match i.e. in Case(X,Y,Z), it only checks if X=Y. However, found a work-around in the Sample Formulas public app: https://login.quickbase.com/db/bcgahn76w?a=q&qid=-5636905&dr=1
To summarize, in my Case(X,Y,Z) example, you can use "true" or "false" as X and simply put the full inequality statement as Y and then Case will compare the "true" or "false" in X against the result of the inequality. Example from the Sample Formulas App:
Case(true, [percent complete]=0,"not started", [percent complete]<1,"in process", [percent complete]=1,"complete","")
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Anthony Guillen
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