Autocad stacked fraction fonts

[harv]

We have used a customized font to create stacked fractions - starting with Autocad 2002. We have a version of Autocad 2010 we were required to buy to work with structural detailing software. When we open a 2002 drawing with 2010, it converts the text that creates the stacked font (ie. %%138 = 1/2) to other text (\U+008A). When the drawing is opened again in 2002, this text does not register in any way (no "question marks" - nothing). All that shows up or plots is the integer part of the number. This created numerous errors in fabrication drawings until we recognized what was happening.

1) Is there a variable within 2010 that can be set so this text is recognized correctly?

2) If not, is there a fraction font available that will work with both 2010 and 2002?

Note: we are not able to create all text as Mtext, so that is not a solution.

[jaberwok]

If your custom font is an SHX file it should work in later versions of acad. You need to create a style in 2010 that uses that font file. Try to copy and paste a piece of affected text from a drawing open in 2002 (or whatever) into a drawing in 2010. The Style definition should come with the text and Matchprop should allow you to apply it to other items.

[harv]

Thanks for the response,
Our custom font is a .shx file. The text style shows up correctly in 2010 (as far as we can tell - using style command, the text style shows up with the correct font file association). I'm not sure I was clear enough in explaining our problem in my first post. I will try to give more detail:
We have a drawing created in 2002 using the special characters described in my first post. Stacked fractions show up properly.
When we open the drawing in 2010, the special characters show up properly as stacked fractions. If we single-click on the text, the properties dialog box comes up and shows the portion of the text that contains the special characters as a square. This seems to indicate that globally these special characters are not recognized correctly. If we save the drawing at this point and open it again in 2002, none of the fractions show and all off the special characters have been converted to (\U+00 ..).
If, when we are in 2010, we double-click on the text, the text editor opens. If we do nothing other than "enter" to close the editor, the text is converted to the correct characters. If we save the drawing and open again in 2002, the text reads correctly.

We are trying to find a global solution to correct this problem. It is unworkable to cut-and-paste a text string into every drawing we open in 2010 and then try to match properties with every text string using the special characters in that drawing.

I can provide drawing files saved in 2002 and 2010 if that would help.

[jaberwok]

The Mtext editor temporarily converts SHX-based text into a TTF-based font for editing. You suggest that your text items are not Mtext so, I wonder if the text editor now works the same way?
One way forward would be to create a ttf font to match the shx font - there is a suggestion here also googling "shx2ttf"
returns a few possibilities (not that I've tried any of them).

[jaberwok]

It is unworkable to cut-and-paste a text string into every drawing we open in 2010 and then try to match properties with every text string using the special characters in that drawing.

That was intended only as a test.