Moved BTree extensions to namespace VelocityDb.Collection.BTree.Extensions.BTreeExtensions. If you are using indexes or doing LINQ queries with BTreeSet, you need to add:
using static VelocityDb.Collection.BTree.Extensions.BTreeExtensions
to your files that does or else index/BTreeSet lookups will be slow. The same extensions are also provided in the VelocityDBExtensions library which is included with source code in the download and now also as a NuGet. To use that code instead of the VelocityDB build in extensions do using static VelocityDBExtensions.Extensions.BTree.BTreeExtensions; instead and you will be able to debug the code and hopefully help us improve this tricky expression tree code.