Ive put a Lowrance Test Chart on my website so that anyone with an older model Lowrance / Simrad/ B&G can see if the charts they make using the IMC will be compatible with their GPS units.
Its here
Just a thought - maybe Matt would consider an option for "compatibility colours only" in the colour selection palette for AT5 export ? Not everyone can afford a new chartplotter every 5 years at 2 grand a pop.
T