I’m using Single Track edi

I’m using Single Track editing. I used the razor tool to create a cut point. Basically I’m trying to remove a flawed section of the video and employ a cross dissolve to bridge the removed piece. I was able to remove the bad clip and slide the remaining video back together and want now to make a J cut with dissolve. Nothing in the documentation said this was not doable. The tutorials I have show how to make the cross dissolve and I followed those instructions, hence the mystery over the "FX Track Blocked…" error message.

Thanks for your help,
Walter