Misterious error on bolt lenght calculation

As far as I know, you should change your spec as follows:

HEADING
NAME TYPE BDIA BTYP BSEL CATREF DETAIL MATXT CMPREF BLTREF TMPREF PDAREF PR$
TREF
DEFAULTS
- - - STUD W


*/BOLT:3 BOLT 20mm STUD W /BOLT-M20 /STUD_BOLT =0 =0 /MSTUD20 =0 =0 =0
*/BOLT:17 BOLT 20mm CAP W /BOLT-M20 /CAP_SCREW =0 =0 /MCAP20 =0 =0 =0
*/BOLT:26 BOLT 20mm NUT W /BOLT-M20 /NUT =0 =0 =0 =0 =0 =0
*/BOLT:4 BOLT 24mm STUD W /BOLT-M24 /STUD_BOLT =0 =0 /MSTUD24 =0 =0 =0
*/BOLT:18 BOLT 24mm CAP W /BOLT-M24 /CAP_SCREW =0 =0 /MCAP24 =0 =0 =0
*/BOLT:27 BOLT 24mm NUT W /BOLT-M24 /NUT =0 =0 =0 =0 =0 =0

This is because when you have BOLT vs CAP, CAP wins !

As far as I know, you should change your spec as follows:

HEADING
NAME TYPE BDIA BTYP BSEL CATREF DETAIL MATXT CMPREF BLTREF TMPREF PDAREF PR$
TREF
DEFAULTS
- - - STUD W


*/BOLT:3 BOLT 20mm STUD W /BOLT-M20 /STUD_BOLT =0 =0 /MSTUD20 =0 =0 =0
*/BOLT:17 BOLT 20mm CAP W /BOLT-M20 /CAP_SCREW =0 =0 /MCAP20 =0 =0 =0
*/BOLT:26 BOLT 20mm NUT W /BOLT-M20 /NUT =0 =0 =0 =0 =0 =0
*/BOLT:4 BOLT 24mm STUD W /BOLT-M24 /STUD_BOLT =0 =0 /MSTUD24 =0 =0 =0
*/BOLT:18 BOLT 24mm CAP W /BOLT-M24 /CAP_SCREW =0 =0 /MCAP24 =0 =0 =0
*/BOLT:27 BOLT 24mm NUT W /BOLT-M24 /NUT =0 =0 =0 =0 =0 =0

This is because when you have BOLT vs CAP, CAP wins !