XML Source File Change Issue (same XSD Different XML Files)

hi all,
i'm facing a small problem with xml file source.
let me explain the scenario!

we have 4 source xml files with same format, each file has around 25k rows of records.

XML Source
Derived Columns
Data Conversion
Conditional Split
OLEDB Destination

its executing fine.
once we change xml file source (second xml file with same xsd),
all other components are showing errors. the error is that

Error 21 Validation error. Staging: DTS.Pipeline: input column "LateRsnCd" (17917) has lineage ID 19380 that was not previously used in the Data Flow task. OnTimeOrderEntry.dtsx 0 0

lineage id has changed it seems, when we are giving new file as xml source. of course xsd is same, but its not taking with names.
to resolve this, if we open that errored task, select all, map using column name--> apply. its getting mapped with the columns as it is in the input.
still the conditional split will show the error.
if we open the conditional flow and give ok, the error has gone, i think some meta dat change has occured in the opening task and giving ok.

what could be the possible probelm and how to fix it?
one more doubt, how can we include xml source in the configuration file? since it doesn't have connection manager, i'm struggling with it for dynamic file selection for xml.
i dont want hard code the source file path (as it reside in the server) in the poperties of the xml source task.
can i have some suggestions please?