Upgrade an old version of theme "total"

Hi,
I have an old version (4.2.1) of theme total and a problem with revolution slider plugin. To solve the problem I need to update the plugin which seems to require the update of the complete theme.
In the description of the update process there is a requirement to also install the “total theme core plugin” .
My questions now:
Is this plugin really required if I do not want to use any new features?
Is there any risk to upgrade the theme in such a big step 4.2.1 to 5.0.8?

thanks for help
Viola

Hi,

Please contact your purchased theme author, theme author will assist you.

How to contact an author to get support or for any technical query:

Thanks