Can you confirm which version of these modules you upgraded from and to ? and also which version of zen-cart you've got ? because ZC may have installed different country codes at different times (certainly has done due to changing political landscapes).
I also do not understand the question as for the Airmail, Airsure and international signed for, they should be split into Europe and the rest of the world right now with no additional modifications needed. I have
Royal Mail defined European Countries
AL, AD, AM, AT, AZ, BA, BE, BG, BY, CY, CZ, DE, DK, EE, ES, FI, FO, FR, GI, GL, GR, HU, HR, IS, IE, IT, KZ, LI, LT, LU, LV, MK, MT, PL, PT, SE, SI, SK, SM, RU, UZ, UA, TM, TR, TJ, CH, MD, MC
Royal Mail defined World Zones 1 & 2 Countries
AX, AF, DZ, AS, AO, AQ,AI, AG, AR, AW, AU, BS, BH, BD, BB, BZ, BJ, BM, BT, BO, BW, BV, BR, IO, BN, BF, BI, KH, CM, CA, CV, KY, CF, TD, CB, CL, CN, CX, CC, CO, KM, CG, CK, CR, CI, CU, DJ, DM, DO, TP, EC, EG, SV, GQ, ER, ET, FK, FJ, FX, GF, PF, TF, GA, GM, GE, GH, GI, GD, GP, GU, GT, GN, GW, GY, HT, HM, HN, HK, IN, ID, IR, IQ, IL, JM, JP, JO, KE, KI, KP, KR, CS, KW, KG, LA, LB, LS, LR, LY, MO, MG, MW, MY, MV, ML, MH, MQ, MR, MU, YT, MX, FM, MN, CS, MS, MA, MZ, MM, NA, NR, NP, NL, AN, NC, NZ, NI, NE, NG, NU, NF, MP, NO, OM, PK, PW, PA, PG, PY, PE, PH, PN, PR, QA, RE, IE, RO, RW, KN, LC, VC, WS, ST, SA, SN, CS, SC, CL, SG, SB, SO, ZA, GS, ES, LK, SH, PM, SD, SR, SJ, SZ, CH, SY, TW, TH, TG, TK, TO, TT, TN, TC, TV, UG, AE, US, UM, UY, VU, VA, VE, VN, VG, VI, WF, EH, YE, YU, ZR, ZM, ZW
and that hasn't changed for about 3 years.
Philip.