WorkBuddy multi-skill chain stalls: quota or permission issue?

Last night at 11 PM, still processing client daily reports, I came across a WorkBuddy installation and multi-Skill chaining tutorial. I wanted to compress reimbursement forms, email attachments, and Excel daily reports into a single CSV following the guide, but I tried running it twice myself and failed.

I've been using WorkBuddy for about a month, but only for file organization. I'm definitely a newbie when it comes to Skills. The tutorial said to first verify if a single sentence could generate a file. I tried it, and a txt file appeared on the desktop, so the environment seems fine. Later, I installed three Skills: PDF, Excel Pivot, and CSV Export. I created an isolated folder, threw in about twenty invoice PDFs and an Excel file sent by a client, and asked it to extract dates, suppliers, and amounts, merge and deduplicate, export to CSV, and then write back a summary.

The first run took about ten-plus minutes, but it only gave me an empty CSV. The prompt seemed to indicate missing field mappings or inability to read some scanned documents. The second time, I broke the task down shorter, extracting only PDFs first. That produced a table, but it broke off when connecting to the next merging step. Some credits were deducted too; the 500 credits shown in the bottom left corner seem insufficient. I wonder if that's the reason.

I want to ask: Does multi-Skill chaining require each Skill to work individually before they can be connected? Or are there pitfalls with local directory permissions, file naming, or field names? Has anyone tried automatically merging reimbursement PDFs and Excel daily reports into a reviewable table? What order is more stable? If it's just that the task description was too long causing the model to get confused, I'll accept defeat tonight. But I have to submit the report tomorrow and really don't want to manually paste things for forty minutes again.