On the EnCo refrigerated container ship, the capacity is listed as "128 nothing" instead of "128 crates cooled goods". Is there any way to convert the .pak file back into the source .dat and .pak files in order to make the necessary edits to fix this and allow the ship to be loaded?
Short answer: no
Long answer: if you can get the source files (if it is an open source pakset or image/dat) then take these and modify them and recompile. Otherwise post a bug report in the board for the right pakset (you didn't say which pak this refers to).
Luckily the freight is coded as ASCII; you may change case errors with a hex editor.
This ship is for pak64, in "Timothy's Ships II", available at the addons site here.
Is there a version of Makeobj compiled for mac? I'd try and fix this, but it's late and the tools are not readily findable. I haven't used Makeobj in some time.
I've uploaded the source files for the ships, not sure why that particular one has broken, may be just changes to the freight categories, or the name of the good type or some kind of thing.
Source files are here:
http://entropy.me.uk/simutrans/enco-light-ships.zip
Timothy: Thank you for making the source available. The problem was an extraneous line in the dat specifying a freight_catg.
Here's the ship (made with Makeobj 50), for any who want it.