The latest version is 2.5.7. Below are links to download these for Mac and Windows.

2.5.7 Fixes installer issues with Windows 64-bit version. Also SHOULD fix some Open Recent File issues.

2.5.6 Fixes the Carry CH. You must import a new bidpack to get the correct data.

2.5.5 adds access to the latest bidpack format (coming in April), as well as indication of top 50% block lines.
2.5.5 fixes Bid Pack Calendar problems (that prevented accessing the past months bid packs).

There are 32 and 64 bit versions. If you have trouble with the 64-bit version, delete it and install the 32-bit version.
BidX Pro 2.5.7 for 32-bit Mac
BidX Pro 2.5.7 for 64-bit Mac
BidX Pro 2.5.7 for 32-bit Windows
BidX Pro 2.5.7 for 64-bit Windows
BidX Pro 2.5.6 for Mac - 32 Bit
BidX Pro 2.5.6 for Mac - 64 Bit
BidX Pro 2.5.6 for Windows - 32 Bit