Re: PDK tools
PDK is no thing but a seriesof script file like spice models for active/passive devices, DRC, ERC, Antenna rules and so on.
to generate it u must have the files and write the others, and of cource it will ahve BUGS so the best way is to use provided pdk of your fab (even in this case u must update it since it have several bug fixes in each version!!!).
BTW, generating PDK will help learning of the tools infra-structure and productivity of the designer.
BEST!