reverse interlinear

Is it that the only way a Reverse Interlinear or Interlinear works is through a Bible version?

Yes - a reverse interlinear is associated with a particular translation.

If the answer to that is yes... then I have several Reverse Interlinears for some versions

What sort of thing are you seeing?

There is typically a reverse interlinear for the OT and one for the NT (and, in some cases, for deuterocanical books). But I'm not aware of any cases where there are multiple reverse interlinears for a particular translation with overlapping ranges.

In WordSearch, I could open a Reverse Interlinear in one pane and my trusty ole NKJV in another pane.... I find that out of all the Reverse Interlinears and Interlinears that I own (which are man) that I cannot find a way to do that in Logos....

What am I missing?

There's absolutely no reason I can think of why one would ever have the RI data in a separate pane next to an English bible. The "R" in RI says that it is a Reverse interlinear, "reverse" meaning it garbles the original language word order and structure to trace back an English (or other) translation's text back to the underlying Greek and Hebrew. Thus, in contrast to traditional, if you will "forward" interlinears, which give say Greek text and translation helps up to a word-for-word crude translation, the reverse interlinears are no library resources but additional lines for the modern bibles for which this dataset exists.

There are several, slightly different RSV or RSV-based bibles, thus there are a number of such RIs. 

EDIT: I own three RSVs with Reverse Interlinears:

• RSV
• RSV, CE
• RSV2CE