Can iSilo™ 2.x or iSilo™ free read documents in the iSilo™ 3.x/4.x document format?
No they can not. iSilo™ 2.x and iSilo™ free can only read documents in the iSilo™ 1.x/2.x document format. However, please note that iSilo™ 3.x/4.x can read documents in the iSilo™ 3.x/4.x format as well as documents in the iSilo™ 1.x/2.x format. If you are currently using iSilo™ free, you may want to consider upgrading to iSilo™ 3.15 or later and use it in free mode so that you can read documents in the newer iSilo™ 3.x/4.x document format.