Rated 5 out of 5 stars

when install the two xpi ,goto usersyle,click" install stylish" ,then install alert "preview/ install/edit/cancle" click install and actually it isnt installed ,you two can fix it,please?

This review is for a previous version of the add-on (0.8.4). 

Yes, I'll fix it

Edit: I should have replied sooner, but I cannot reproduce your issue.
All three buttons work fine on Firefox v35 with Stylish-Custom v0.8.4 and Stylish v2.0.6.

"preview/ install/edit/cancle" probably means you aren't using the correct version of something.

Edit2: Ohhh I've never tested SC with SEM, doubt they would work together well, and you probably shouldn't use them together. Of course it's up to you.