LPC17xx: "Cannot stop processor" using JTAG after undefining "CLOCK_SETUP"

I have been developing my project with LPC1768 since months, actually coding bootloader. I tried to reduce code size to fit in 4kB sector and turned off code for configuring PLL in the file: "...\CrossWorks for ARM\packages\targets\LPC1000\include\CMSIS\system_LPC17xx.c" by setting:

#define CLOCK_SETUP           0

because i have it defined once again in my code. Since this time I lost control over my micro using JTAG (compatible to Amontec).

Now I know it was bad idea. I should rather reduce my code then the start up one. Actually when I try to download and start corrected code (with defined CLOCK_SETUP) I receive information in the "Output" window:

Build complete
Preparing target for download
Loading target script file LPC1700_Target.js
Executing reset script FLASHReset()

After it on the status bar is displayed information in red: "Cannot stop processor".

I tried to download the correct hex file using JTAG download command. In this case receive similar info "cannot stop CPU". Tried to slow down JTAG increasing clock divider and re-power device - all without success. 

Hardware (wires) are correct. I can connect and work normally with other device not affected by this fatal code change.

I  have defined in my preprocesor:

STARTUP_FROM_RESET
USE_PROCESS_STACK

My CrossWorks Studio relase is 2.0.10.2011011700.9509

Package is "NXP LPC1000 CPU Support Package" v1.17. Also tried to re install it to refresh system files - without succes.

Do you have any ideas how to recover from this situation?