KB005432: Message ‘Gene Identifier’ column is needed while trying to create a Custom Technology-Genespring GX 

Gene Identifier is mandatory for the creation of custom technology.
In the step 4 of 9 of custom technology creation, select the correct identifier column from data file.
Also, a column which has the same values as the Identifier column in the annotation file must be selected in Step 9 of 9.
The column which is common in both the files  should be used as identifier in step 4 and step 9.
For more information on creating custom technology, please go through the chapter 15 and 16 for Generic Single Color and Two Color Technology Creation from the GeneSpring manual.