This doesn’t even compile. You have use strict but then don’t declare %HoA or $venue.

it seems to hang on the 'split' line

No, even if you get it to run, it never reaches the split line: the preceding line:

next unless s/^(.*?):\s*//;
[download]

skips all the input lines, because none of them contain a colon as specified in the regex.

Also note that you cannot write to a filehandle which has been opened for reading only. See:

• open
• Opening Text Files for Writing
• How come when I open a file read write it wipes it out?

Hope that helps,