Issues cloning my primary site into a subsite

Dear all,

I have a primary site which I think is quite heavy. I have tried to use various plugins like cloner, multisite copier and snap shot but I keep getting timed out.

For content copier, I just get to discover it does not copy all the files
for cloner same thing and for snapshot messages as in attached file.

Thanks in advance

Please I need advice on how best to go about this.