Kerning about mactype HOT 5 OPEN

You're right, there is a significant difference of font arrangement between 
mactype and gdipp.
generally speaking, gdipp places letters based on freetype width, while mactype 
places letters with Windows GDI32 width. As you can see, freetype outputs a 
more accurate value in most cases, therefore gdipp can make a better kerning of 
characters. However, all the programs are originally designed based on GDI32 
width (ClearType width), if you force the letters to be rearranged by freetype 
width, there will be a mess in display. gdipp solve this problem by hooking a 
lot of GDI32 width related APIs, but there are always some exceptions making 
gdipp works weird like "letter 'i' is missing...", "the cursor is inside a 
letter".
mactype use GDI32 width to arrange letters so that you can create an office 
document with mactype enabled and open it in another PC without mactype, and 
both of them looks identical.

For whatever reason, your MacType text looks slightly worse than mine: 
http://ace.mpql.net/screenshots/2012-05-10_00-53-26.png

I felt like sharing in case a better comparison could be made.

Is there a possible planned solution for this? I obviously understand not 
having widths match up will cause some problems when the length of text is 
important, but the awful kerning is also a big problem.

Some rare bugs are preferable to the kerning issues in that screenshot.  A 
missing 'i' does not make me cringe, but bad kerning is painful.  Of course, a 
cursor inside a letter isn't good either.  I hope you find a solution.  This 
bug is the main thing holding mactype back from greatness.  If only all fonts 
were monospaced...

"a cursor inside a letter" bug has been fixed in the develop version. And about 
kerning, you need to blame windows for its awful hinting and positioning system.