Good to see you take on the challenge, Chris !
We'd have no chance !!
Just found some
interesting tools on their site ! (Go to bottom of the page and click on the "Explore Cosmology" useful link. Look for 'QuickStart Calculator' and 'QuickStart Tutorial').
The calculators allow you to 'roll your own' Cosmology !!
The
Tutorial gives a really good overview on Lensing, also.
Cheers