Why do errors persist/

I'm using RoboHelp 2015, trying to generate Webhelp.

I keep having a problem where something goes wrong and RoboHELP insists on keeping the wrongness. For example, I had a bulleted list that had a graphic in a line of text. When I generated Webhelp, the graphic was missing - all I got was the "no graphic" icon. I edited the list and re-imported the graphic, and regenerated Webhelp - same result. I manually edited the code on that list line to re-import the graphic - same result. I tried resizing the graphic - same result.

I tried creating a second copy of that line in the list. This time, the graphic showed in the Webhelp. But when I edited the list again and took out the original line, the one that I had copied, once again the graphic was missing from the Webhelp.

No matter what I did, as long as that line was inside that bulleted list, that one graphic refused to appear in the Webhelp. The only way I could finally get it to show reliably was to delete the entire bulleted list - all nine lines - and manually recreate it.

I keep having this kind of problem with RoboHelp 2015. I have a project in which there are dozens of places where the ONLY way I can make something work right is to delete all HTML code for that thing and recreate it on a different line. There are dozens of places where things appear correctly and links work perfectly in the "Preview Topic" pane, but when I generate an output of any format, those things are broken. This is killing my productivity and I am now at risk of missing a very important deadline? What is going on here and HOW CAN I STOP IT?