I have few doubts about CM Build

I'm new to CM build.
Currently i have a working source and i'm able to build a cm without problem.
Weekly once i sync the repo and build the new nightly build.

Here are my doubts.
1.Do i need to clean the source before each build? like make clobber or make clean
2.Two zip files get produced at end of each build cm-*nightly.zip and cm-*-ota.zip,whats the difference between them?

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Unable to upload files in latest RR M-v5.6.1-20160112 build

Hello

Flashed the latest ResurrectionRemix (M-v5.6.1-20160112) ROM yesterday. Previously was on the last build of RR Lollipop, and everything was working fine. After the update, I have not been able to attach files or send images via email apps (Gmail, Cloudmagic) and messaging apps (Whatsapp, Hike). 75% of the upload is completed and then it just stays that way till I get a message asking me to retry.

Any suggestions?

Thanks in advance

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Sprint/Galaxy Application - Who can build?

I need an application for incoming calls that can perform an immediate answer, immediately send a “1” tone, then complete the call to a smartphone?

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