No, I pretty sure not, as it was 2005 I did this as my accounts have since been done by a professional accountant and I was never asked any questions.
Basically I opened a new current account for my business as I wanted to keep all transactions seperate. So, when I had to use personal funds to buy equipment/services, I just wrote a cheque from the business account to cover it. Same as if someone in a PAYE job accrues expenses paid for with personal funds, the employer usually just writes a company cheque.
Bear in mind that I'm a sole trader so it may be slightly different in so far as all money coming/going is 'mine' as such anyway, so the fact that I'm just balancing accounts shouldn't make a difference. As long as they're legitimate expenses you should be fine.
As for categorising it in the accounts... I just put the invoices through as normal, claimed the VAT as normal, and then recorded them as expenses for end-of-year accounts as normal? Shouldn't be any issue there.