It seems that no matter if the code is written in C or C++. I'm working with last link plugin (4.1.2.201701141320) and jlink driver (v6.14). The issue seems to be related to the number of opened projects. If I just imported the PSU (lpc_xxx projects are necessary to build) everything goes well.

However in the next scenario I'm not able to debug the PSU project, as shown in the previous post.

I've also used another debug probe (P&E Multilink Universal with its latest eclipse plugin & driver) with the same (bad) results. So It seems the issue does not related to the jlink tool
Lack of memory problem maybe? (I'm running on W7 Professional 32-bit and 3GB RAM)
I will continue investigating anyway...
regards,
gaston