I've installed the enhanced point of sale from bazaar and I would like to make the choice of the client mandatory like with the POS_Cashiers module (that does not work in my setup) on POS screen, best if selected from a very specific client list. Any tip?

Thanks.

https://code.launchpad.net/~mmakonnen/openobject-addons/point_of_sale_enhanced-70
http://thierry-godin.developpez.com/openerp/tutorial-module-creation-pos-modification-english-version/