I do the following,

1. I take a original cd and click on copy image & create cuesheet.
2. When finished I click on write cd, I load the cuesheet, pick burningspeed (2x or 4x) and burn the cd.
3. Now I'm trying to make a image of the burned cd. There's a problem, sync error etc.

What did I do wrong?

I'm using a Nec ND2500A with frimware 1.09.

I've tested it with cd's from TDK, Platinum, Sony and Philips.

I configured EAC with online configurations.

I use the EAC095b2dao.

Can somebody help me

Synchronisation error should not cause too many problems. Of course, purists could get mad about them, but I don't care. I do usually have synch errors at the end of the last track. But I don't hear anything to worry about.

HTH.

The problem is probably that your CD-RW drive is damaged or unreliable, or the disc you wrote is damaged or just plain lousy.

I don't see the point of burning at such a slow speed. I've seen nothing to suggest that this improves the quality. To burn a great quality CD you need a CD writer & good media. The NEC is not known for it's CD writing capability, mine certainly didn't do a great job.
The quality CDs I produce are using my old liteon burner @ 40x with Verbatim Pastel or Super AZO media. Audio CD media is also good (but expensive).