I have recompiled r22404, and can confirm that GCPs and coordinate systems are now read successfully for all the following tested scenes:
MER_FRS_1PNRAL20100426_091349_000000822088_00494_42632_0001.N1
MER_RR__2PNPDK20100519_101302_000005462089_00323_42962_4158.N1
MER_FR__2PNEPA20030714_102918_000000982018_00094_07162_0053.N1
MER_RR__2PNPDK20110515_100806_000004953102_00281_48140_3923.N1
MER_RR__1PNRAL20100426_154828_000003662088_00498_42636_0001.N1
Prior to the update it worked only for the MER_FR-scene.
I believe the ticket can be safely closed. Thanks a lot!
Note: the archive of sample MERIS-files has in the meantime moved to:
http://www.brockmann-consult.de/cms/web/beam/meris-products