On IWP objects tend to need a little more layout space. Maybe the radio button set is simply a bit too small.
That is what I thought also but it does work. What is funny is you can see ok if you are allowed to use it for entering.
I cannot duplicate the problem with either Firefox 3.0.5 nor Internet Explorer 7 running Windows XP SP3. This is what I have done:
1. I created a database with a table that includes a Text field "Radio".
2. I created a Value List entitled "Yesno" with custom answers "Yes" and "No".
3. I went into Layout Mode and set the field "Radio" to display as a Radio Button and assigned the value list "Yesno".
4. I went into Browse Mode and added a couple of records.
5. I returned to Layout Mode, selected "Radio", went into Format -> Field/Control -> Behavior and unchecked the options for "Allow field to be entered: In Browse mode" and "in Find mode". I returned to Browse Mode to verify.
6. I turned on Instant Web Publishing.
7. I went to a Windows machine and launched Firefox 3.0.5 and opened the database. The "Radio" field shows with the options, even though I cannot select them. I then launched Internet Explorer 7 and I was able to see the field.
8. I went to a Macintosh machine and launched both Firefox and Safari, and I'm able to see the "Radio" field.
If there is a set of values you want me to try, let me know, and I will try to duplicate the problem.
The only thing that I have done differently is created/design from a MAC. Could it be a font issue? I will try this in a clean database. Also this database in hosted on 9 server, if that helps.
I just created this on an iMac with all the same steps above. The font I used was Verdana. What font are you using? I'll try to duplicate it here.