Using "New BglAnalyze" V1.0.0.1 I can partly disassemble the BVCF bgl file. However, I get allot of errors when decompiling. It says "Error: Unknown Subrecord in Boundry". I believe this unknown sub-record is what I'm looking for. The following is from the decompiled bgl:If I look at the BVCF bgl with notepad, I can see the actual name of the center. Such as follows:X 2133(FDD S

The

The missing section is a Com segment. This must have been created with something other than BGLCOMP since BGLCOMP will not allow a Com segment in a Boundary section.Also FS9 is very picky about BVCF.BGL. If I delete the first Center entry leaving the rest intact it does not recognize any Centers at all.

I think we don't know about all commands needed for the ATC structure. The SDK does not seem very complete there. MS probably never intended us to extend/change that file.The fact that the COM command is not allowed there, is probably a fault in the XSD file, as you should be able to create any BGL that uses the Fs2004 XML format with BGLComp.

I don't believe that a COM can be associated with a boundary.I used a hex editor to look at a boundary in a BGL file and found that it matches the description given with NewBGL with no provision for a frequency item.Each boundary comprises a "header" record and a "line" record that describes all the lines forming the boundary. The header record varies with the length of its name - the size of the name + 6 is given at offset 34. There is a DWORD at offset 2 of the header record which gives the total length of the boundary record (header record plus line record). The line record consists of a fixed 8 byte header with following 10 byte records for each individual line forming the boundary. There is a DWORD at offset 2 of the line record which gives the length of the line record, and a WORD at offset 6 which gives the number of lines forming the boundary.There is no space allocated for a frequency. A DWORD would have to be inserted somewhere to hold its value. This would require all subsequent data items to be shifted by 4 bytes. The whole structure of the BGL files suggests to me that FS expects to find its data at specific offsets from the start of a record and so will/can not deal with the case where the offsets to the same items vary. EDITThe description of the structure of NewBGL identifies the maximum and minimum latitudes and longitudes and these are in the BGL file but NewBGL (V1.0.0.1) doesn't extract them.