Which reference are you actually talking about? You can use the LEGO design ID directly in the Mecabricks search field. For decorated elements, you can often use the BrickLink reference or LEGO element ID (when data has been entered).

Hi, I'm talking about the code which is on the parts page at the end of Lego instructions - I think this code denotes the brick and the colour. So, for example, Lego code 4595708 is a Trapdoor Frame 6x8 in dark bluish grey. If I put 4595708 into Mecabricks search I get no result. If I put it into Bricklink it gives me their code which is 92107 and tells me the colour. I can then find the part in Workshop using the bricklink code and then select the part colour. Also, note that bricklink states the part colour is "Dark Bluish Grey" which doesn't seem to exist as a colour in Workshop unless it has a different name? I hope that makes sense.

The LEGO element ID is only used for decorated elements on Mecabricks as much as we can. That is just impossible to maintain this list with hundreds of thousands of references. Bricklink is a company that has been around for like 20 years and their index is not exhaustive either.

Mecabricks uses the official LEGO material names (as found also on brickset). Bricklink has his own naming system. See Mecabricks colour chart including conversion.

Thank you - I can see how keeping the database update must be a full time job - there are a lot more people at LEgo generating this stuff that on your team adding them into Mecabricks!