ZB4 Brush issues

[s_o_u_t_h_e_r_n]

I seem to be having really odd errors when using the Move Brush.

ZB4 new install and tried on two systems.
MacBookPro and an Imac 27" both less than a year old running the latest version of Snow Leopard.

When trying to use the MOVE BRUSH I get what I think is a graphic error which disappears when I rotate the model.

See below:

http://www.theunityartist.com/topost/zberror.mov

Any ideas?

[s_o_u_t_h_e_r_n]

Weirdly the 10.6.4 seems to have solved it on the macbook pro.