Greasy Fork

Can control page number everytime ?

When use this script to download some book, some preview books are OK, but the other is fail
One fail case , preview page is 536, once start to working to 130+, it hunging there ,
I think , maybe page is a little big, Can I control page number , eg : only 50. ?

Thanks

Then, hunging is means : not pop infomtion:
alert('Downloaded every available page out of '+ number + ' total. Saving…');

Do not know why, maybe get picture took too long . and there are some control
to prevent this issue?

Thanks again