i also use WH4L and have been for a number of years. indeed the issue of first time compilation of DNN is an issue of concern specially for low traffic sites,
WH4L provides a ping service to activate the compilation of ther asp.net/dnn engine every 20 mins. but they charge 20 $ a year per dom ain.
i discovered a better way
get the wget.exe file, place it in ur Win OS folder
creat a cmd batch file (using a text editor)
run a macro scheduler to run the cmd file
& u can activate as many website as u like! and u can schedule the time (i.e instead of 20 every 10, or switch it off if ur traffic increase, cuz u do not need it)
alternatively u can purchase from snowcovered a commercial module (cleint site) for as little as 10$
the choice is urs.
if u need further info make another post!
have fun