Have you tried using keyboard shortcuts? The short cut for the crop tool is "c". You can find all of the shortcuts under the Fireworks menu.

I've never heard of any Adobe product having an intermittent problem. Have you installed any third party add-ons? Is the caps lock key engaged?

I use Fireworks, but not the CS3 version so I've not seen the problem.

I would contact Adobe support because there may already be a reported issue on this topic and a possible resolution/workaround available.

Yes, I have that problem, Accelerator. It seems to be a known issue in which the mouse pointer is offset on the screen, i.e., where you see the mouse pointer is not where the software thinks it is.

It appears to be due to the way Adobe handles your screen resolution setting. I found my problems began when I moved to a 1920x1200 laptop running Windows 7. Viewing in the native resolution would likely make stuff too small, and Windows resizes the views. Adobe seems to choke on that. I've tried various solutions, none of which have been a permanent fix. Oddly, it seems to work properly about 5% of the time. Every time that happens, I think it's fixed... until the next time I use Fireworks, and it's back to the offset.

Just had CS5 upgrade delivered, I think that will cure it (but at a cost!).

One recommendation is to open Fireworks using "Run as Administrator." Wasn't a permanent fix for me, but it apparently helped others. Here's some discussion at Adobe:
[forums.adobe.com...]

Thanks for all the replies guys. I am running non-standard resolutions so the mouse pointer explanation makes sense.

Rgds

Is there any way to address this without spending huge amounts of money on new software?

Try hitting Space Bar when you get stuck. Works for me.

To close the loop on my own Fireworks CS3 saga, I finally did upgrade to CS5 (a brutal 5-hr load from DVD!) and the inability to click stuff due to the mouse pointer offset vanished. Works fine now. Too bad it's an expensive product.