I have a loss bought forward to my 2017/18 tax return from rental income & will have a profit this year which is less than the loss carried forward, so will be carrying forward a loss - is it true that there is a problem with the software on Gov.uk that means this loss carried forward has to be entered in the 'additional information' section and will not be therefore shown as a loss carried forward in the calculation sheet?
Yes you can only input a loss that is equal to the total profit recieved in the year. The working for the total loss carried forward to future years can only be detailed manually in the additional information box. Take care to avoid using sybols like '£' or any new paragraphs as these can prevent you from progressing forward inside the return. This information is also details in the '?' tooltip online.