OK, how about this.
I thought about your problem and your desire to not have to redo all the report each day and month.
I think excel can still be your main program for this data. I considered your current skills set and think you may appreciate staying in excel if it can do what you have asked. Dates are notoriously difficult to deal with in access, so i thought excel would be better for the task of calculating closing and opening stock values.
Have a look at the excel workbook now. Post back here if you have any questions about how the formulas work or anything you need changed.
I have created a single "Data" sheet where all your manually entered values are input each in a separate column. This sheet also has all the calculated values in columns but they are hidden. you can unhide them by auto-sizing the columns in the sheet. New days are a new row (you must add new days to the very next available row so formulas are copied for each day).
The data is set into a "Table", which allows new rows to copy any formulas from the rows above. these formulae automatically detect new months for the monthly cumulative data, so the formulae don't need to be changed at all.
I have also considered that you may want/need the report in the format you had. So i created a new sheet called "Report" and all you need to do is add the date of production in the highlighted yellow section and it will auto-fill with all the data from the "Data" sheet for the correct date. You must make sure to type the date correctly so that access recognizes that you have used a date not another number. I have formatted it in such a way that any value greater than zero will be highlighted in green so that you can easily distinguish those cells with a value and those with three decimal zero value (0.000 vs 5.346 = much easier to read/see if highlighted IMHO). I also added a red highlight in case there are any values less than zero, to prompt you to double check your data entry or to alert you of a negative in your production.
What do you think. I think this is a much simpler solution that gives you what you said you wanted. It is also possible to do things like create graphs to have summaries etc, which is much, much harder in access.
Please note: For the "Data" sheet, any field with calculations i have formatted in grey. You had some discrepancy/change between july and august how two fields were handled (manually updated vs. calculated) so i kept this discrepancy in the new sheet which is why you see only two grey cells. I have not always understood why you have calculated the way you have, but i have made the same calculations for you in the "Data" sheet because i assume you understand your data much better than i do.
Also, i have left your original sheets in tact. i had to format the cells in such a way so that i could see which ones had a formula so i could walk through your data easier. if you want to remove this formatting, go to the conditional formatting menu and remove the formatting there.