Might be your remote. I have somewhat slow response time from my Pioneer SR-90 (780 milliseconds for complete reliability), However that remote is notorious for being extra difficult to decode. I set it to 380 and have about 85% reliability (sometimes a long press gets interpreted as two short ones). With the Rio Remote from my Empeg I set it to 250 and get 100% reliability. 250 millisecs is pretty fast, not quite as a keyboard, but theorectically you could press and get proper response for 4 presses per second. These timings are the ones that you set up in the RemoteMappings.ini file. I would try to set up the Rio Remote in Wirlirc and then map it to EMSC and see if the response is acceptable to you. If it is, then you know that that the problem lies with the remote.

To make the computer hibernate, or standby, instead of shutdown:
1) right click on empty space on the screen
2) select properties
3) screen saver tab
4) select the "power" button
5) select the "advanced" tab
6) where it says "when i press the power button in my computer", select hibernate or standby.

I think standby is OK unless youre not going to use the car for several days. My computer is playing music within 12 seconds (including the 5 second delay that the opus PS adds) of turning the ignition.