[kube]

Hi roc. It's late my brain is fried - I should go to bed. So I have no ideas what I am typing...

There are 2 locations for txt_login_incorrect
1. skin1/modules/Fast_Lane_Checkout/checkout_0_enter.tpl
and 2. skin1/main/error_login_incorrect.tpl

Assuming that the purpose of having 2 different coloured versions of txt_login_incorrect is to differentiate between a registered user or not, use...
{if $login} logged in error colour {else} anon/loggedout colour error {/if}

It is preferable to use webmaster mode to locate .tpls. Webmaster mode is best used with IE (Internet Explorer), with popups enabled, and 'view>status bar' enabled.

Hope this helps.