September 14 is not the best day to be learning the rules of electronic filing for a return due the next day.  The Regulation requiring that statement was written in 2000 or earlier, in the days of paper business returns.  But now, all the answers are in Pub 4163.  See pages 60-62.  You just need to learn them.  

3.26 Creating Elections/Disclosure Statements Required by Regulations or Publications
MeF requires all disclosure statements and elections to be included in preparation software and transmitted to the IRS in one file.
To allow companies to add additional information on their return, IRS created a “General Dependency”
Schema. The General Dependency has a defined format and should be used by the taxpayers to report
most disclosure statements and elections required by regulations or IRS publications. The General
Dependency Schema format is provided to Software Developers for their preparation software, and
developers should provide instructions for completing this Schema to its users.

3.27 Preparing Elections and Disclosure Statements That Require Supporting Data
Some elections and disclosure statements require supporting data that cannot be entered into a General
Dependency Schema. IRS allows this data to be submitted as a PDF file. The actual disclosure statement and election must be entered into the required format, and only the supporting data may be submitted as a PDF file.