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misterhaan: ah, that’s why i only see one achievement on portal 1 — that’s the only one with a date, and it's april 2011. it’s probably an issue with the steam integration that they expected there to always be a date with achievements; nice that it didn’t just crash the whole thing!

fun fact steam also didn’t give me the fruitcake achievement for beating 4 advanced maps but it did later give me the vanilla crazy cake achievement for beating all 6.
Most likely issue with the integration but please submit mantis ticket through the Report Issue button in the Client.