This page of dotCover options summarizes general settings of the dotCover environment.
Application icons theme
These radio buttons let you switch between different sets of dotCover UI icons. You can leave the default option of automatic selection or choose an icon set that will be most comfortable for you for the selected Visual Studio theme.
Source code symbol icons theme
These radio buttons let you switch between different sets of code symbol icons. You can leave the default option of automatic selection or choose an icon set that will be most comfortable for you for the selected Visual Studio theme.
Show managed memory usage in status bar
If this checkbox is selected, the amount of managed memory used by the whole process is shown in the rightmost position of the status bar. This value indicates not only the amount of managed memory used by ReSharper but also the amount of managed memory used by other third-party plug-ins and Visual Studio itself.
Store solution caches in
dotCover caches a lot of its temporary data. If you do not share the solution, you can choose solution folder. If you share your solution using a VCS, it is better to choose the system temp folder so that dotCover gets them out of the solution folder and therefore out of the way of your VCS. It is recommended to choose a custom folder. The problem with the 'User local settings folder' %LOCALAPPDATA% is that Visual Studio's directory watcher could be triggered when ReSharper writes to this folder, which happens very often. You need to reopen your solution for changing caches location to take effect.
Clears the cache of the current solution. Normally, you do not need to clear solution cache, but some events (for example, sudden power off or an upgrade that skips several versions) may corrupt the cache, and that's when you need to use this button. Signals of corrupted cache may be a lot of unresolved code or absence of dotCover inspections in some files. After clearing the cache you need to reopen your solution and wait a little while dotCover rebuilds the cache.