I installed this version v1.75-RC2 and I noticed two flashes on the screen while writing a private message on the forum. It is possible that this is a bug in JavaScript from another modification installed.
Update to v1.76I don't see any flashes on the screen when attempting to write a post or PM.
What you can do is just disable snowflakes for those actions.
Imo it's not a big deal if the effects are not visible when users are actually writing a post or PM.
It will still show when they are reading PM's or browsing the forum posts.
Go to the Snowflakes admin and find the input box for:
List actions/subactions to disable Snowflakes (comma separated)
enter the following & save the settings.
post,pm~send