Why not use your macro to open the file then call the macro you want directly afterwards.
To open a file for import then execute another macro afterwards use this code.
Workbooks.OpenText Filename:="C:Filesmyfile.txt", Origin:=xlWindows _
, StartRow:=1, DataType:=xlDelimited, TextQualifier:=xlDoubleQuote, _
ConsecutiveDelimiter:=False, Tab:=True, Semicolon:=False, Comma:=False _
, Space:=False, Other:=False, FieldInfo:=Array(1, 1)
Call mymacro
Hope this helps