.sts file has forgotten and I can't edit styles
Hello. I am using FM 2015 in a Win 10 environment.
I had an .sts file that was working pretty well to convert FM output to HTML Help.
Now it has forgotten what it knew (it has lost the settings). Our PDF template uses a side column with right-aligned headers; our help output has one text column and headings should be left-aligned. I set up the alignment using the "Block" setting.
Now that seems to have been erased from the .sts file (along with everything else) and when I select H1, for example, and click the Edit Style button, nothing happens.

Can anyone shed any light on this? Thanks.
