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In comment lines starting with the letter C, operators, keywords and alternative keywords are coloured [color=red:7fd1d84b71]red[/color:7fd1d84b71] or [color=blue:7fd1d84b71]blue[/color:7fd1d84b71] and not black like the rest of the text line.
Plato needs to know if it is a fixed format or free format file. In this case I assume that Plato thinks it is a free format file whilst you intend it to be fixed format.
From the Tools menu, select Options and then Text Editor and Language settings.
Under Fixed format Fortran you will see a list of file extensions that Plato assumes are fixed format. Add your file exension to this list.
I had done that. Added ';.for' (without quotes).
Anyway my posting was just a curious observation. This new behaviour was not in Plato V4.1, and in fact the comment lines were then in [color=green:d296987b20]green[/color:d296987b20].
More information. If I choose only fixed format FORTRAN the file types used are not correctly displayed (the free-format ones are still there with tab position 4). If I ignore this and do not add my file type '.for', Plato3 displays the correct colours and accepts my source files.
The .ini file correctly lists the fixed-format file types (Filters=.for;.f;.ins) and tab position (6).
Plato V4.1 shows the same, or similar, behaviour. I don't know whether this is a recent change. I didn't notice it before.
I am confused. .for should be available by default. Try removing the entry from the ini file.
I am happy to leave it, because it works despite what the Language form says. I also notice that if I click on the text, 'Fixed format fortran', rather than just the tick box, the correct source file types appear only to revert to the Free format versions when I re-open the Language form.
I wonder if you have misunderstood the idea.
The name of the file should have a .for extension. For example, myfile.for. Plato, as well as FTN95, will understand this as a fixed format Fortran file.