I've done a BWP install as well ; customized the install order so that that all components other than global changes are installed early but after BGT. Global changes are installed quite late in the process. Full weidu log :
Checked changelog of Bow of Marksmanship and Eagle Bow, they do seem to be changed only by the Fixpack, followed by BGT and finally Item revisions :
Mods affecting BOW07.ITM:
00000: /* from game biffs */ ~BG2FIXPACK/SETUP-BG2FIXPACK.TP2~ 0 0 // BG2 Fixpack - Core Fixes: v9.01 BWP Fix
00001: ~SETUP-BGT.TP2~ 0 0 // Baldur's Gate Trilogy - Core: 1.12 (12 Jun 2011)
00002: ~ITEM_REV/ITEM_REV.TP2~ 0 0 // Item Revisions by Demivrgvs: V3 Beta 1
00003: ~ITEM_REV/ITEM_REV.TP2~ 0 14 // Remove Cleric Weapon Restrictions from Multi-Classed Clerics: V3 Beta 1
00004: ~ITEM_REV/ITEM_REV.TP2~ 0 17 // Weapon Changes: V3 Beta 1
00005: ~ITEM_REV/ITEM_REV.TP2~ 0 1080 // Enchantment Doesn't Affect Speed Factor of Weapons: V3 Beta 1
Note that I did not install any "big" mod (TDD, NtoSC, etc), quest mods, item mods, etc. Content-wise, this is mostly the original saga, plus tweaks, fixes and IA. ToBex did get installed twice (I guess SCS already checks if it has been installed previously), but I'm not sure if it would affect the game (both were v20).
I'll try to start a playthrough this week-end.
EDIT : and I have no idea why the spoiler tag won't hide my log...