Version 4.x and LOWER of the ActiveX version of Xceed Zip has a limitation of 4 gigs and 65535 files.
Even if you use the SplitSize property to create multiple parts, the limitation remains the same. If the split zip file surpasses the limitation, Xceed Zip will not be able to unzip the contents.
As of version 5.0, Xceed Zip supports the Zip64 format. The Zip64 zip file format is the 64-bit counterpart of the zip file format that is used by PKZIP 4.5 and up. It supports up to 2^64 -1files within a zip archive as well as files that have a size greater than 4GB for a zip file size that can reach up to about 18 million terrabytes ( more precisely, 264 -1bits).
Xceed Zip for .NET and Xceed Zip for .NET Compact Framework also supports Zip64.