Create New Template based on t3_bs3_blank

Hi all

Any tips and advice for creating new template:

I am using t3_bs3_blank
I am trying to rename it,
However, the language files do not seem to like it and I end up with the T3_TPL_DESC_1, T3_TPL_DESC_2, T3_TPL_DESC_3, T3_TPL_DESC_4
instead of the language override.

I have changed all references from t3_bs3_blank to my template name but no joy.

Thanks for any help