Why does my custom IP not automatically re-synthesize?
Previous to 11.1, there was the CORE_STATE option in the pcore's MPD file that told the tools to regenerate the core. This option is described in the Platform Studio Reference Manual. The CORE_STATE option is deprecated in 11.1. The new option and syntax is:
OPTION ARCH_SUPPORT_MAP = (OTHERS = DEVELOPMENT)
Add the above line to your core's MPD file.