I can confirm this bug. It worked fine for me a week before. It seems to be a bug in one of the latest beta.

Thanks for fixing it

2015-04-13 19:45 GMT+02:00 Mojca Miklavec <mojca.miklavec.lists@gmail.com>:

The following example works in MkII and it works in TeX Live 2014, but
it fails with the latest beta (it draws a black rectangle instead of
using the defined colour):

\fill[mycol] (0, 0) rectangle (2,4);

It would be really nice to fix this in time for TeX Live 2015.

Thank you,
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