This may be a quibbling point, but it is a valid quibble all the same.
Quote:It was when a doctor at the Changi Hospital suggested that she appy/applied for the Hospital Endowment Fund that a light shone brightly for her at the end of the tunnel.
"A light at the end of the tunnel" is a well-worn metaphor. The phrase has been used so often that it has become a cliche, a metaphor with the wit and illumination worn away.
When you add "brightly" you aren't freshening the metaphor. You're inserting an unfamiliar element that makes the reader slow down and look at the words your using rather than what your words are saying.
Also the usual usage is "she could see a light at the end of the tunnel". Once again, when you change the usual phrasing you jolt the reader.
As for "it was when"--you've used three words when only one, "when" is needed.