MathML questions

["Duncan Hothersall" <dh@capdm.com>]

I've been very impressed with the ability to set MathML mark-up with
ConTeXt, but in contrast to when I had my own translation running, where I
could find and fix bugs myself I find it much more difficult to fix things
that are going wrong now (although much less is going wrong anyway...)

I have two questions:

1. How can I fix an entity not being rendered? When I use, e.g. unicode 22C5
(a ċ), they come out as the word "sdot" in a frame. When I look in
base/xtag-meb.tex the definitions all look right (\defineMMLentity sdot
22C5 {\cdot} ...) but the output doesn't seem to work.

I'm using the default CM font settings so I don't think it's that, and lots
of other special characters render well, so I assume it's a definition
problem but can't identify it. Is xtag-meb.tex loaded by default with MathML
processing, and if not, how can I load it?

2. When using visual rather than semantic mark-up, large equations,
especially with mtable elements in them, seem to generate a lot of

! Missing \right. inserted.

errors. I can post code if necessary, but does this ring any bells?

Thanks much,

Duncan