On question 1, SRS light, your air bag shouldn't be bad. One of the threads I found using the search function, above, was SRS Light Stays On For 1 minute after starting car...
There were a number of others, so if this doesn't help, you might try the search yourself and see what you find.
On the Rough Idle, another search found that the OVP may be a problem. That thread is C280 Nightmare
. Again, there were more, so the answer might be burried in there as well.
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