Problem with lighting installed in grand church (6)
I believe the answer is:
glitch
'problem' is the definition.
(I've seen this before)
'with lighting installed in grand church' is the wordplay.
'with lighting' becomes 'lit'.
'installed in' indicates putting letters inside.
'grand' becomes 'g' (synonyms).
'church' becomes 'ch' (common abbreviation).
'g'+'ch'='gch'
'lit' going into 'gch' is 'GLITCH'.
(Other definitions for glitch that I've seen before include "Flaw" , "Sudden malfunction in equipment" , "Unexpected setback" , "Minor mishap" , "Temporary equipment malfunction" .)