Alexey Berkovsky wrote:It’s just behavior of the cursor. In case of Version 5 if the cursor is clicked over the sign “+” the text is expanded. In version 7 it happens only after the click on the hyperlinked text
I just checked this and it is working fine in Help+Manual 7.
No skins were selected for this project...
That is the problem.

This means that you are using the old templates and scripts from your old Help+Manual 5 version that are still embedded in your project. You either need to reset the page template in your project (Configuration > HTML Page Templates > Default) or just select one of the CHM skins included with Help+Manual 7. Selecting a skin disables all the internal templates and settings that have correspondences in the skin and replaces them with the skin versions.