I know that some ProSeries users use Form 6198, but other than perhaps using it as a worksheet to calculate the amounts, Form 6198 should not be filed if the loss is limited due to Basis.

ProSeries does not support Basis losses.  That means you are supposed to manually calculate the allowable loss (or perhaps temporarily use 6198 as a worksheet to figure it out), then enter the allowable loss on the K-1, and manually carryover the unallowed losses to next year.

As for why the 6198 (as a worksheet) is showing the entire amount as allowed, I'm not sure.  Perhaps you are entering something wrong?