By following this post, I had some issues.
When compiling nrf_ppi.h:
1) For channels 10, 11, 12, 13, 14, 15: 'PPI_CHEN_CH10_Pos' undeclared here (not in a function); did you mean 'PPI_CHEN_CH1_Pos'?
When compiling the nrfx_timer.c:
1) 'NRF_TIMER3' undeclared (first use in this function); did you mean 'NRF_TIMER0'?
2) 'TIMER3_CC_NUM' undeclared (first use in this function); did you mean 'TIMER0_CC_NUM'?
Any idea, please? Thank you very much.