Total-Based Shipping - error

I have just installed the Total-Based Shipping extension but keep getting the error
Error: Could not load model shipping/totalbased!

I have set it up as follows in UK Shipping
35:3.99, 60:6.00, 100:8.00, 115:0.00

Is this correct above?
so items total under 35.00 is 3.99 postage
35.01 to 60.00 is 6.00 postage
60.01 to 100.00 is 8.00 postage
and over 115 is free postage

forgot web address
www.health-wellbeing.net/wecaneco/

well not sure what i have done apart from re-upload files and tested and all is working

It's possible a file didn't upload completely when doing it the first time, which resulted in the error. Glad it's working for you now

Thanks Jonathan