It's not clear to me if you're physically in Bahrain right now or just from there. If you're local, then honestly, I don't think online is the right place to start. I mean, sure, start up a mailing list or Facebook group, or whatever platform most Bahrain residents use. But network in person to get people to join.
Set up a free open meeting to share each other's films or slideshows. Have a projector or a computer linked to a large TV screen that takes flash drives or other media. Put a time limit on each contribution (5 mins or 10 mins, depending on how many people you think you'll have). Moderate it well. Leave some time for questions and discussion. Serve snacks!!
Collect everyone's email addresses and send regular followups with info about upcoming meetings and links to whatever place you have discussions.
Repeat monthly, maybe in different parts of the country.
You can also do this online, either on Facebook or a YouTube channel or another forum.
After a while, you'll get to know the people who you want to approach about collaboration. And the coolest part is you're helping develop the next generation of filmmakers/graphic designers too.