Out of curiosity which language did you have to set?
Natlink engine's implementation should automatically get the current language from Dragon through the Windows COM interface. Credit goes to Danesprite for this portion of answer.
0x0c09: ("en", "AustralianEnglish"),
0xf00a: ("es", "CastilianSpanish"),
0x0413: ("nl", "Dutch"),
0x0009: ("en", "English"),
0x040c: ("fr", "French"),
0x0407: ("de", "German"),
0xf009: ("en", "IndianEnglish"),
0x0410: ("it", "Italian"),
0x0411: ("jp", "Japanese"),
0xf40a: ("es", "LatinAmericanSpanish"),
0x0416: ("pt", "Portuguese"),
0xf409: ("en", "SingaporeanEnglish"),
0x040a: ("es", "Spanish"),
0x0809: ("en", "UKEnglish"),
0x0409: ("en", "USEnglish"),
Note older versions of Dragon may support fewer languages.
Supported languages for Dragon NaturallySpeaking 15 products
Retail Editions:
Dragon Home 15
English
German
Dragon Professional Individual 15
Dutch
English
French
German
Italian
Spanish
Dragon Legal Individual 15
Australian English
English
German
New Zealand
Dragon Professional Group Single User 15
Dutch
English
French
German
Italian
Dragon Legal Group Single User 15
English
German
Enterprise Editions:
Dragon Professional Group 15
Dutch
English
French
German
Italian
Dragon Legal Group 15
Australian English
English
German
New Zealand
Dragon Law Enforcement Group 15
English