Problem with collectionFS and CDN

My Meteor application has implemented with collectFS and use CFS:filesystem as storage.

Uploading/downloading files worked as long as using server IP address or DNS name with no CDN configured.

However after putting CDN (CloudFlare), downloading became extreme slow, almost impossible to finish, and upload was just stuck at begin, then never moved an inch forward, database has record showing item, with no content.

Has anyone ran into such issue as using CDN + collectionFS

The cause for this problem is not collectionFS. Sorry for that