I always was angry about the implementation of the start-time and end-time for particles so i made a pull request and now you can make start and end time for each particle file. ( The pull request is already implemented )
The new syntax is:
<particles value="true" start-time="0.8" end-time="1">
<particle-file path="particles1.xml" start-time="0.28" end-time="0.5"/>
<particle-file path="particles1.xml"/>
</particles>
The times of the individual files overrides the times of the particles node.
If someone has nothing better to do he can add this to all
skills in the wiki 