Jolee,
If you want to generate HTML reports to be shown in the browser to the user who generates the reports, the easiest option is to use object presentations. They are very similar to reports. In fact, their design is compatible, so you can simply export design of an existing report and import it into an object presentation. Please refer to the Aware IM User Guide for details on object presentations.
You can also generate certain reports with Word templates by using functions SUB_DOCUMENT, LIST and LIST_TABLE inside template tags, which work similarly to sub-reports. Please refer to Aware IM User guide for details on these functions. You can try using function LIST with an Excel template and see if it produces a satisfactory result. It may or may not, depending on your formatting requirements. You cannot generate reports with multiple items using an HTML template because the LIST function will not work with it properly.