[Bug] Lyndor doesnt continue download if there is multiple attachments

[itsmemac]

Added a list of 30 courses and started the download and went afk
When i returned to see if the course has been downloaded and to my surprise it was struck
in the 3rd course download for 6 hours as it had multiple attachments and it didn't proceed further
Had to manually download the attachment and remove the already downloaded 3 courses from bulk download.txt and run lyndor to continue.

Please fix this issue.

[itsmemac]

if there is 3 attachments in the course, it downloads 1 & 3 but leaves 2
if there is 2 attachments in the course, it downloads only 1

[ankitsejwal]

I will test it soon, can you provide some sample URLs. Thanks

[itsmemac]

https://www.lynda.com/Substance-Designer-tutorials/Substance-Designer-Essential-Training/601765-2.html
https://www.lynda.com/Substance-Painter-tutorials/Substance-Painter-Essential-Training/496947-2.html
https://www.lynda.com/Unreal-tutorials/Unreal-Substance-Designer-Workflow/653218-2.html