The rocket parts are just regular units in the CIV5Units.xml.
If you want to change their production costs in the modpack, open the override file and search for <Type>UNIT_SS_BOOSTER</Type> and so on, and set the <Cost>1500</Cost> to whatever value you prefer.
Thanks so changed some values in the modpack and playing a game with my brother atm ...
so last thing are the parts ... which are major unbalanced. I found in the modpack following settings :
Seems the
<InstanceCostModifier>0</InstanceCostModifier>
could change the value, but does anybody know, which values are valid ?
As it is a modifier,
it could be
1 to any value in %
... so changing that to 100 means 100% more to pay
or is it a multiplicator ?
like "2" means costx2
or only a value like cost + "InstanceCostModifier"
Damn would need a savegame, where I could test it

Thank you
<Row>
<ID>56</ID>
<Type>UNITCLASS_SS_COCKPIT</Type>
<Description>TXT_KEY_SS_COCKPIT</Description>
<MaxGlobalInstances>-1</MaxGlobalInstances>
<MaxTeamInstances>-1</MaxTeamInstances>
<MaxPlayerInstances>1</MaxPlayerInstances>
<InstanceCostModifier>0</InstanceCostModifier>
<DefaultUnit>UNIT_SS_COCKPIT</DefaultUnit>
</Row>
<Row>
<ID>57</ID>
<Type>UNITCLASS_SS_STASIS_CHAMBER</Type>
<Description>TXT_KEY_SS_STASIS_CHAMBER</Description>
<MaxGlobalInstances>-1</MaxGlobalInstances>
<MaxTeamInstances>-1</MaxTeamInstances>
<MaxPlayerInstances>1</MaxPlayerInstances>
<InstanceCostModifier>0</InstanceCostModifier>
<DefaultUnit>UNIT_SS_STASIS_CHAMBER</DefaultUnit>
</Row>
<Row>
<ID>58</ID>
<Type>UNITCLASS_SS_ENGINE</Type>
<Description>TXT_KEY_SS_ENGINE</Description>
<MaxGlobalInstances>-1</MaxGlobalInstances>
<MaxTeamInstances>-1</MaxTeamInstances>
<MaxPlayerInstances>1</MaxPlayerInstances>
<InstanceCostModifier>0</InstanceCostModifier>
<DefaultUnit>UNIT_SS_ENGINE</DefaultUnit>
</Row>
<Row>
<ID>59</ID>
<Type>UNITCLASS_SS_BOOSTER</Type>
<Description>TXT_KEY_SS_BOOSTER</Description>
<MaxGlobalInstances>-1</MaxGlobalInstances>
<MaxTeamInstances>-1</MaxTeamInstances>
<MaxPlayerInstances>3</MaxPlayerInstances>
<InstanceCostModifier>0</InstanceCostModifier>
<DefaultUnit>UNIT_SS_BOOSTER</DefaultUnit>
</Row>