Default CRJ-700 Localizer and VOR Display Questions

I've noticed when flying a localizer or ILS approach in the default CRJ-700, the localizer deviation on the PFD as depicted by the HSI is different than as indicated by the pink localizer diamond display near the bottom of the attitude indicator. For example, when the pink diamond shows the a/c is off course (off the center of the localizer) by 1 dot, the HSI shows a course error of 2 dots. I would have expected both displays to agree "dot for dot". Does anyone happen to know what is the case in the RW CRJ-700, and how many degrees of deviation each diamond and HSI dot represents when in localizer mode?

 And as a related question, in the RW CRJ-700 how many degrees of deviation does each HSI dot represent when tracking a VOR ( vice localizer ) signal?

Interestingly, the default 737-800 and 747-400 exhibit the same localizer dot/diamond difference as the default CRJ-700 (I'd guess because they likely share the same gauge code), but the PMDG 737NGX does not. The 737NGX diamond and HSI localizer displays agree dot for dot.

If someone with RW CRJ-700 experience can comment on the above that would be great.

Thx,

Al