[Alan_SP]

You have small error here:

<b><if condition="$post[field6]"><img src="$stylevar[imgdir_misc]/$post[fieldX].gif" alt="$post[fieldX]" /></if></b>

<b><if condition="$post[fieldX]"><img src="$stylevar[imgdir_misc]/$post[fieldX].gif" alt="$post[fieldX]" /></if></b>

You should also check if there's value specified in certain (X) field, not 6 specifically. Typo I'm sure, but could confuse some people.

Also, you need to mention that images has to have same name as values you have. It's important for different languages. So, if site uses different language, file names have to be changed accordingly. And in case of special characters it could be a problem, if it is not supported by OS, file couldn't be named with them, so you need to use different words to describe gender.

And just my opinion about section where it is posted, this is template modification, not a mod.